Conventional food waste disposers are typically coupled to a sink by a mounting gasket, which is typically composed of rubber. The mounting gasket serves as the primary seal between the sink and the disposer and preferably also prevents the transmission of vibration from the disposer to the sink.
In a prior art approach, and referring to FIG. 1, a conventional connecting assembly 40 and rubber mounting gasket 80 are used to attach the disposer to the sink 30. The conventional connecting assembly 40 of FIG. 1 is substantially similar to that described in U.S. Pat. No. 3,025,007, which is incorporated herein by reference. The connecting assembly 40 includes a sink collar 34, a seal plate 50, a mounting flange 60, and a support flange 70.
During assembly, the sink collar 34, seal plate 50, and mounting flange 60 are first secured in place around and underneath the sink 30. More specifically, the sink collar 34 is positioned within the drain opening 32 of the sink 30, leaving drain flange 36 to rest around the drain opening 32 as shown. During assembly, a gasket 54 and the seal plate 50 are slipped onto the sink collar 34 now appearing on the underside of the sink 30. The mounting flange 60 is then slipped onto the collar 34, and a snap ring 62 is seated within an annular recess on the collar 34. Studs 66 are then screwed through threaded holes 64 in the mounting flange 60 until they contact the underside of a projecting surface of the seal plate 50, thus pressing the gasket 54 between the seal plate 50 and the sink 30. (Three studs 66 are normally used, but only one is shown in the cross section of FIG. 1). The mounting flange 60 has inclining flanges 68 onto which the remainder of the disposer (and associated hardware) can be screwed to fix the disposer into position underneath the sink, as will be explained in further detail later.
The food waste disposer includes a container body 10 and a top container cover 20, both preferably formed of metal. The container body 10 has an outwardly extending lip 12 to which edge 22 of the container cover 20 is crimped to seal the top of the disposer. The container cover 20 includes a housing collar 24 that forms the inlet of the disposer. During assembly, the support flange 70 is positioned on the housing collar 24 of the housing, and the mounting gasket 80 is press fit onto an outwardly extending lip 26 of the extruded collar 24 to hold the support flange 70 in place. As shown, the support flange 70 contains inwardly bent tabs 78.
When the disposer (with the support flange 70 in place) is to be affixed to the mounting flange 60 (already supported under the sink), the tabs 78 are positioned to meet with the inclining flanges 68 on the mounting flange 60. Because the inclining flanges 68 are inclined, the tabs 78 (i.e., support flange 70) can be twisted with respect thereto, in effect, screw the disposer onto the mounting flange 60 to position the disposer in place underneath the sink 30. To facilitate turning the support flange 70, the support flange 70 is preferably formed with finger pads 76. (Again, the support flange 70 normally contains three sets of tabs 78 and finger pads 76, but only one such set is shown in the cross-section of FIG. 1). As the support flange 70 is twisted into place, it is brought closer to the mounting flange 60 due to the incline of inclined flanges 68, thereby compressing the mounting gasket 80 therebetween, and further compressing the mounting gasket 80 against an inwardly projecting flange 38 of the collar 34. In short, the flanges 60 and 70 compress the mounting gasket 80 to create a seal between the sink collar 34 and the housing collar 24 on the disposer. The mounting gasket 80 includes a plurality of pleats 87 formed across the drain opening to keep food waste from being ejected through the drain when the disposer is operating.
Food waste disposers produce noise during operation that is caused by the operation of the motor and by the impacting of food waste against the housing of the disposer. These sources produce vibrations having a broad frequency spectrum. The vibration of the disposer can be transmitted into the sink through the connection of the disposer with the sink, which produces objectionable noise in and around the sink. Such noise is particularly evident, for example, in installations with relatively thin stainless steel sinks that act as excellent resonators.
Unfortunately, the conventional connecting assembly 40 and mounting gasket 80 of FIG. 1 create a substantially rigid connection between the food waste disposer and the sink. In particular, vibration is hypothesized to travel through the solid metallic housing collar 24, the compressed mounting gasket 80, and the connecting assembly 40 to the sink 30. Although vibration through the collar 24 is somewhat attenuated by the rubber material of the mounting gasket 80 that surrounds it, further dampening measures would be desirable, particularly if such measures did not significantly impact the structural integrity of the disposer or the manner in which it is affixed under the sink.
The reader is referred to the following U.S. patents for further background concerning ways of minimizing operation noise of food waste disposers, all of which are incorporated herein by reference in their entireties: U.S. Pat. Nos. 2,743,875; 2,894,698; 2,945,635; 2,951,650; 2,965,317; 2,975,986; 3,801,998; 3,862,720; and 5,924,635.